Honestly, Docker Swarm is so great. We use it with 6 very beefy machines (each 1tb memory/96cpu cores) for years already. It's so stable and well done, no restarts, crashes, or weird behaviors. We use it in a Hetzner VLAN and performance is excellent. We are very satistfied with it, and I would use it for even bigger scenarios. I even thought about building something like coolify/flightcontrol on top of it, so I can really easy have proper deployments of my stuff